In Thailand, civic groups, journalists and opposition politicians are vowing to fight new government emergency measures aimed at quelling 18 months of violence in three southern provinces. Thai security officials say the measures are necessary because the attacks are becoming more sophisticated and more deadly, but critics fear the government will use the situation to roll back democratic freedoms.

Night was beginning to fall last Thursday in Thailand's southern city, Yala, on the eve of Friday prayers when a series of explosions plunged much of the town into darkness.

In the 30 minutes that followed an estimated 60 attackers rampaged through the town, firebombing hotels, shops and a police booth. Two policemen were killed in a shootout and 22 civilians were wounded.

The following day an angry Prime Minister Thaksin Shinawatra announced his government would pass a new law granting emergency powers to control the unrest.

Government spokesman Chalermdej Jombunud says the government for some time has wanted to overhaul a group of old laws, decrees and emergency measures, in order to unify the chain of command and strengthen security efforts in the south.

"We combined seven laws together to become the new royal decree," he said.

The measures, which replace martial law in three southern provinces, allow authorities to detain suspects without charge, ban public protests, listen in on phone calls, and censor the media. The law also gives legal immunity to officials who carry out such acts.

Security officials fear that the southern violence, once considered to be a mix of quarrels among local Muslim separatists, criminal gangs and corrupt officials, could be reaching more dangerous levels.

A professor at Bangkok's Chulalongkorn University, Panitan Wattanyagorn, says the attackers have become more sophisticated and better organized.

"They are now behaving very much like a terrorist group or a terrorist movement, not yet fully emerged as a well-organized organization, but they are on their way to becoming one impressive organization very soon if not controlled properly," he said.

The roots of the violence lie in long-standing resentments among the original inhabitants of the region, ethnic Malay Muslims, against the central government of predominantly Buddhist Thailand. Separatist rebels waged a guerrilla war in the 1970s and '80s. The violence subsided in the 1980s under an amnesty but re-emerged early last year with a raid on a military base in which hundreds of weapons were taken.

In the 18 months since then, more than 800 people have been killed. An estimated 100 local leaders have disappeared. And security forces have been accused of excesses that have aggravated the tensions. In October, attacks intensified after 85 men died following a demonstration, most of them while being transported to detention centers.

Experts say the insurgency so far has been mostly a local movement with little influence from outside Thailand. However, Professor Panitan says this is changing.

"It is more and more understood that these groups are not just local groups anymore," he said. "They have now been assisted or connected in various ways, especially in terms of charity and tactics. And this is making a new dimension in the south."

The secretary-general of the Islamic Center of Thailand, Prakorn Preeyakorn, says most Muslims in the south are living in fear and support government efforts to end the violence.

"Most of them do agree with the government's move at the moment. But they think [it better] if the government can control the situation without violating human rights," he said.

However, the new law has brought protests from civil rights activists, intellectuals and journalists, who fear the government will use it to undermine democracy.

The chairman of the Senate Foreign Affairs Committee, Kraisak Choonavan, says the new law will not end the violence.

"Terrorists, the insurgents are a very small number and yet they are able to prolong and increase their activities because of people's support," he said. "Now, if you continue to intimidate the people with this law which will make intimidation legal, you will see no end to the insurgency."

Senator Kraisak says the insurgents' aspiration for their own state has been boosted in part by international Islamic militancy, but he says support for the insurgents has been especially strengthened by the security crackdown.

The Thai government in recent months has pursued a policy of dialogue in the region. It appointed a reconciliation commission, which has recommended lifting martial law to ease public resentment toward the central government. And despite the new law - which some members view as a setback to their efforts - the commission says it will pursue its efforts to bring an end to the violence through peaceful means.